B777 FBW flight envelope protection
bsevenfour we differ only in our simplifications; the problem is far more complex than we have discussed.
Crossunder and Fullwings have adequately replied to the A320 and 777 points. The issue is not within the system’s switching, but the failure of the crew in any aircraft to ‘switch on’ to changing conditions or circumstance.
CFIT, how hard to pull? The crew rarely see the ground until it is too late; the best design philosophy is to fit EGPWS and train not to activate any alert.
Fighters pulling ‘g’? See the recent photo of a F16 at the bottom of the loop (pulling xx ‘g’) as the pilot switches to a 'Martin Baker' design after a misjudgement.
Crossunder and Fullwings have adequately replied to the A320 and 777 points. The issue is not within the system’s switching, but the failure of the crew in any aircraft to ‘switch on’ to changing conditions or circumstance.
CFIT, how hard to pull? The crew rarely see the ground until it is too late; the best design philosophy is to fit EGPWS and train not to activate any alert.
Fighters pulling ‘g’? See the recent photo of a F16 at the bottom of the loop (pulling xx ‘g’) as the pilot switches to a 'Martin Baker' design after a misjudgement.
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quote:
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If they had pushed the thrust levers forward instead of waiting for the aircraft to add thrust, nothing would've happened.
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Now let me describe what would have happened on a 777. If they were doing a low fly-by below 100ft letting the speed come back to the stall. They firstly would have got warnings of the low airspeed situation. If they continued to let the speed bleed off the autothrust would 'wake-up' and try to regain the airspeed. Now lets take the worst case scenario where the autothrust system was switched off at any stage if they had pushed the thrust levers forward manually they would have got increased thrust. All completely intuitive.
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If they had pushed the thrust levers forward instead of waiting for the aircraft to add thrust, nothing would've happened.
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Now let me describe what would have happened on a 777. If they were doing a low fly-by below 100ft letting the speed come back to the stall. They firstly would have got warnings of the low airspeed situation. If they continued to let the speed bleed off the autothrust would 'wake-up' and try to regain the airspeed. Now lets take the worst case scenario where the autothrust system was switched off at any stage if they had pushed the thrust levers forward manually they would have got increased thrust. All completely intuitive.
If they had pushed the thrust levers forward instead of waiting for the aircraft to add thrust, nothing bad would've happened. (because they would have got the increased thrust)
